368 Mn South' s re-examination of the apparent distances 



No. XXVI. R. A. 17^ 56" ; Decl. 2° 33' nI " 



70 p Ophiuchi ; 11. 4 ; H. and S. 258 ; 



continued. 



The mean of both series, allowing each a weight propor- 

 tioned to the number of measures, gives for the 



Epoch 1825.56 ; Position 58° 3' 5/(105 measures.) 

 Distance 4^765 (71 Obs.) 



If now we collect all the observations made in the years 

 1821, 1822, 1823, and 1825, we find as follows : 

 1821.51 ; 66° 50' 5/; (Mean of Herschel's, South*s, and 



Struve's Obs. Phil. Trans. 1824. iii. p. 290. 

 1822.49 ; 65"" i sj\ H. and S. 1822, 

 1823.32; 63 25 sj\ H. and S. 1823. 

 1825.54 ; 58 3 sf\ S. ut supra. 



The intervals are 0.98, 0.83, and 2.22 years, and the 

 Angles described respectively in them — i°.7i7, — i°.70o, 

 and — 5°. 36 7, whence the angular velocities come out re- 

 spectively — l°.75i, — 2^050, and — 2°.4i8, all of them 

 greatly below what appears to have been the velocity up to 

 1820, and not differing more than might fairly be expected, 

 considering the difficulty presented by the unequal size of 

 the stars. The last determination, considering the great 

 number of measures it rests upon, may be regarded as en- 

 titled to great confidence, in spite of the discordant results of 

 April 3 and May 3, 1825, which, however, whether rejected 

 or retained, make little difference in the final mean. It was 

 on these (unluckily), that the note at the end of the paper of 

 J 824 was founded. 



The fact of a great diminution of angular velocity then in 



